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1.
建立了悬浮固化分散液液微萃取(SFO-DLLME)结合高效液相色谱(HPLC)快速测定水样中6种邻苯二甲酸酯(PAEs)的分析方法。通过对影响萃取效率因素的优化,确定了最佳萃取条件:十二烷醇萃取剂20 μL、萃取温度60℃、离子强度20 g/L、萃取时间1 min。6种PAEs在2~2000 μg/L范围内呈良好的线性关系,相关系数(r)为0.9995~0.9999,检出限(S/N=3)为0.3~0.6 μg/L。对自来水、湖水、江水、污水、海水、市售塑料瓶装纯净水和矿泉水进行测定,能检测到部分PAEs。对加标水样进行回收率试验(10、100和1000 μg/L),6种PAEs的回收率为84.9%~94.5%,相对标准偏差为4.1%~6.8%(n=5)。该法环保、简单,可用于实际水样中6种PAEs的检测分析。  相似文献   

2.
固相微萃取/高效液相色谱联用分析水样中邻苯二甲酸酯   总被引:17,自引:2,他引:17  
研究了固相微萃取(SPME)/高效液相色谱(HPLC)联用测定环境中痕量邻苯二甲酸酯的分析方法,比较了5种不同类型涂层对5种邻苯二甲酸酯的萃取效果,采用3因素3水平正交实验设计对SPME的条件如萃取时间,离子强度,解吸时间等进行了优化,SPME优化的条件为:65μm聚二甲基硅烷/乙烯苯(PDMS/DVB)涂层,室温,搅拌速率1100r/min,萃取时间30min,纯乙腈解吸,解吸时间2min。HPLC的条件:C18反相色谱柱,乙腈-水(体积比60:40)梯度淋洗,流速1mL/min,紫外检测波长228nm。方法 的线性范围为0.50~80.00μg/L,检出限为0.11~2.20μg/L,相对标准偏差(n=6)为2.5%~9.6%,用于自来水、凉开水和雨水等实际水样的分析,回收率为82%~128%。  相似文献   

3.
研究了固相微萃取(SPME)-高效液相色谱(HPLC)联用测定水样中痕量苯并(k)荧蒽的的分析方法。对SPME的条件如萃取时间、萃取温度、离子强度、解吸方式、解吸溶剂、解吸时间和HPLC条件进行了优化,建立了SPME-HPLC联用分析水样中痕量苯并(k)荧蒽的方法,并用于自来水、雨水和纯净水等实际水样的分析。SPME优化的条件为室温、搅拌速度1100r/min、萃取时间30min、甲醇解吸溶剂、解吸时间2min。HPLC的条件为C18反相色谱柱、甲醇流动相、流速1mL/min、紫外检测器、波长244nm,以峰高为测量信号。方法的线性范围为0~8.00μg/L,检出限为0.014μg/L,相对标准偏差(n=6)为6.7%,回收率为82.0%~104.2%。该方法适合于水样中痕量苯并(k)荧蒽的分析。  相似文献   

4.
建立了固相微萃取-气相色谱质谱联用测定聚碳酸酯树脂中环境雌激素4-枯基苯酚和双酚A的分析方法。优化了固相微萃取纤维、萃取温度和时间、解吸时间、搅拌速度、pH等萃取条件及衍生化温度和时间、衍生化方式等衍生化条件,并对样品浸泡时间、浸泡温度等进行了研究。方法的线性范围为0.05μg/L~1mg/L,4-枯基苯酚和双酚A的检出限分别为50ng/L和0.5ng/L,相对标准偏差(RSD,n=5)分别为5.2%和1.6%,平均回收率(n=3)在90.50%~107.3%之间,该方法简单、快速、灵敏。  相似文献   

5.
固相萃取-气相色谱法测定北京市水样中的邻苯二甲酸酯   总被引:16,自引:0,他引:16  
研究了使用毛细管柱(OV-1701)分离、FID作为检测器的气相色谱法测定水中5种邻苯二甲酸酯(PAEs)[邻苯二甲酸二乙酯(DEP),邻苯二甲酸二丁酯(DBP),邻苯二甲酸丁基苄基酯(BBP),邻苯二甲酸二(2-乙基己基)酯(DEHP),邻苯二甲酸二环己酯(DCHP)]的色谱条件。5种PAEs检出限在0.1~0.3μg/L之间,所测PAEs的质量浓度在0.5~100μg/L范围内,RSD在2.2%~3.3%之间,各物质校正曲线(质量浓度与峰面积)的相关系数在0.9970~0.9993之间。利用固相萃取技术萃取水中PAEs,回收率在82.5%~110.5%之间,RSD在1.1%~4.0%之间。北京市吴家村污水处理厂4个采样点中邻苯二甲酸酯浓度在(0.7~193.3)μg/L之间。北京市南护城河的3个采样点中邻苯二甲酸酯浓度在(0.1~241.8)μg/L之间。  相似文献   

6.
本文建立了固相萃取-气相色谱法定量分析地下水中酞酸酯类(PAEs)有机污染物的方法。利用正交试验和单因素实验对影响回收率的4个主要因素(洗脱溶剂种类、水样体积、洗脱溶剂体积、固相萃取小柱填料量)进行了萃取条件的优化。综合考虑各方面因素后确定的最佳萃取条件为:二氯甲烷和丙酮为洗脱剂,体积8mL、0.5L水样、柱填料500mg。方法线性范围0.05~10.00μg/L,检出限0.05~0.341ng/L,相对标准偏差0.038%~1.107%。该方法应用于江汉平原地下水中PAEs测定,取得满意结果。  相似文献   

7.
利用顶空固相微萃取与气相色谱联用技术(HS-SPME-GC)以富勒烯聚二甲基硅氧烷(PSO-C60)固定相处制萃取头分析了塑料浸取液中的邻苯二甲酸二(2-乙基)己酯(DEHP),并对萃取温度、离子强度、吸附时间和热解析时间进行了研究。结果显示,该方法的线性范围在5μg/L-500μg/L,检测出了为2.8μg/L,相对标准偏差为4.8%(n=6).  相似文献   

8.
三氯乙醛在常温下加碱能快速转化为三氯甲烷,通过测量三氯甲烷建立了顶空固相微萃取气相色谱法间接测定水中三氯乙醛的方法。探讨了水中三氯乙醛萃取效率的影响因素,如温度、萃取时间和加盐量等,并确定萃取温度为40℃、萃取时间为5min和3g加盐量作为实验的优化条件。实验结果表明,在0.50-20.0μg/L范围内线性关系良好,方法检出限为0.08μg/L,实际水样加标回收率为103%-120%,测定结果的相对标准偏差不大于2.5%(n=5)。该方法操作简单,重现性好,可用于地表水中三氯乙醛的测定。  相似文献   

9.
应用可忽略耗损固相微萃取与高效液相色谱联用技术测定了环境水样中双酚A的自由溶解态浓度。为了获得高的灵敏度并减小环境因素(如温度和搅拌等)的影响,采用商品化固相微萃取纤维CW/TPR进行平衡采样。在环境水样常见pH(5~8)、缓冲容量(5~200mmol/L)和盐度(0~500mmol/L)条件下,4h可以达到萃取平衡。100mL样品足以避免样品耗损。以配制在250mmol/L NaCl和125mmol/L磷酸盐溶液(pH6.4)中的双酚A标准溶液进行校准,可以将缓冲液(0~200mmol/L)、盐度(0~500mmol/L)和pH(5.7~8.5)的影响控制在15%偏差范围以内。如需更准确的测定,也可以对样品pH值的影响加以校正。pH为6.4时,方法的线性范围为0.1~250μg/L,检出限为0.03μg/L,相对标准偏差(5μg/L,n=3)为1.1%。采用本方法测定了污水处理厂排水口的双酚A的自由溶解态浓度。  相似文献   

10.
刘芃岩  高丽  申杰  刘微  蔡立鹏 《色谱》2010,28(5):517-520
建立了固相微萃取(SPME)-气相色谱法(GC)分析环境水样中痕量邻苯二甲酸酯类化合物(PAEs)的方法。选用100 μm聚二甲基硅烷(PDMS)萃取纤维,在磁力搅拌条件下,对水样中的PAEs萃取富集60 min,然后直接注入GC进样口,在250 ℃温度下解吸4 min后进行分析测定,13种PAEs能得到充分提取和分离。方法的重现性(以相对标准偏差(RSD)计为0.2%~9.7%,检出限为0.02~0.83 μg/L。将本方法应用于白洋淀水样中PAEs的分析检测发现,样品中邻苯二甲酸二异丁酯(DIBP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)检出率相对较高。对水样进行两个浓度水平(2.5 μg/L和5.0 μg/L)的加标试验,加标回收率为75.3%~111.0%,RSD为2.1%~8.0%(n=3),能够满足环境水样中痕量PAEs的测定要求。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
19.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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